Wearable airbag device

ABSTRACT

A wearable airbag device includes a holding body adapted to be worn by a wearer, a gas generator held by the holding body, and an airbag that is held by the holding body and includes an inflatable portion which is inflatable with an inflation gas from the gas generator. The inflatable portion includes a lower inflatable portion for protecting the hip of the wearer, an upper inflatable portion for protecting the head of the wearer, and a communicating portion that is in gas communication with both of the lower inflatable portion and upper inflatable portion. A regulating element is disposed in the communicating portion so as to control a flow of inflation gas so that the upper inflatable portion is inflated after inflation of the lower inflatable portion. The gas generator is configured to deliver the inflation gas more toward the lower inflatable portion than toward the upper inflatable portion.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority from Japanese Patent Application No. 2020-165660 of Kawamura et al., filed on Sep. 30, 2020, the entire disclosure of which is incorporated herein by reference.

BACKGROUND 1. Technical Field

The present disclosure relates to a wearable airbag device that is adapted to be worn by a wearer and configured to deploy an airbag in order to protect the hip and the head of the wearer in the event of a fall of the wearer.

2. Description of Related Art

JP 2000-317002 A and WO 2010/090317 A1 discloses a wearable airbag device that is configured to deploy more than one airbag in order to protect such body parts as the hip, head, and sides when sensing a fall of the wearer (an elderly person, by way of example) by an acceleration sensor and an angular velocity sensor. The airbags are configured to be inflated by an inflation gas fed by a gas generator. WO2011/148354 A1 discloses a wearable airbag device that includes an airbag that is configured to be deployed for protecting the chest, back and neck of the wearer.

A wearable airbag device with a plurality of airbags as taught in the two former references referred to above would require corresponding number of gas generators. Such a device would resultingly be heavy and bulky, thus has a room for improvement to be implemented as a wearable airbag device. On the other hand, in a wearable airbag device that includes one each airbag and gas generator in order to protect various body parts as taught in the latter reference, the airbag would have a big volume and require a long time to be fully inflated. Such an airbag device may fail to be inflated adequately to protect the various body parts.

Therefore, it would be desirable to provide a wearable airbag device that is able to protect the hip and head of a wearer adequately in the event of his/her fall with an airbag and a limited number of gas generators.

SUMMARY

An exemplary embodiment in the present disclosure relates to a wearable airbag device including: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and is configured to discharge an inflation gas; and an airbag that is held by the holding body and includes an inflatable portion configured to be inflated with the inflation gas fed from the gas generator. The inflatable portion of the airbag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer; and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion. The airbag further includes, in the communicating portion, a regulating element that is configured to control a flow of the inflation gas so that the upper inflatable portion is inflated after inflation of the lower inflatable portion. The gas generator is configured to deliver the inflation gas more toward the lower inflatable portion than toward the upper inflatable portion.

Another exemplary embodiment in the present disclosure relates to a wearable airbag device including: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and includes a gas discharge portion that is configured to discharge an inflation gas; and an airbag that is held by the holding body, the airbag including an inner bag that includes an inflatable portion configured to be inflated with an inflation gas fed from the gas generator, and an outer bag that has a bag shape and covers an outer circumference of the inner bag. The inflatable portion of the inner bag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer, and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion. The outer bag includes: a connecting covering portion that is tubular in shape and covers an outer circumference of the communicating portion of the inner bag; an upper covering portion that is continuous with an entire circumference of an upper end of the connecting covering portion and is configured to cover an outer circumference of the upper inflatable portion of the inner bag as inflated; and a lower covering portion that is continuous with an entire circumference of a lower end of the connecting covering portion and is configured to cover an outer circumference of the lower inflatable portion as inflated. The gas discharge portion of the gas generator is disposed in the lower inflatable portion of the inner bag so as to inflate the lower inflatable portion prior to the upper inflatable portion. The lower inflatable portion of the inner bag is stored inside the lower covering portion of the outer bag. The upper inflatable portion of the inner bag is stored in the connecting covering portion of the outer bag and is configured to move into the upper covering portion of the outer bag and be inflated at rise of an internal pressure of the lower inflatable portion caused by collision between the lower inflatable portion as fully inflated and the ground at falling of the wearer.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a schematic front view of a wearable airbag device in accordance with the first exemplary embodiment.

FIG. 1B is a schematic back view of the wearable airbag device of FIG. 1A.

FIG. 2A depicts an airbag for use in the wearable airbag device in accordance with the first exemplary embodiment in a standby state.

FIG. 2B depicts the airbag of FIG. 2A as actuated.

FIG. 3 illustrates the deployment process of the wearable airbag device in accordance with the first exemplary embodiment at falling of the wearer.

FIG. 4 illustrates the inflation process of the airbag of the first exemplary embodiment.

FIG. 5 illustrates the inflation process of a modification of the airbag of the first exemplary embodiment.

FIG. 6 illustrates the inflation process of another modification of the airbag of the first exemplary embodiment.

FIG. 7 illustrates the inflation process of yet another modification of the airbag of the first exemplary embodiment.

FIG. 8A is a schematic front view of a wearable airbag device in accordance with the second exemplary embodiment.

FIG. 8B is a schematic back view of the wearable airbag device of FIG. 8A.

FIG. 9A depicts an airbag for use in the wearable airbag device in accordance with the second exemplary embodiment in a standby state.

FIG. 9B depicts the airbag for use in the wearable airbag device of FIG. 9A as actuated.

FIG. 10 illustrates the deployment process of the wearable airbag device in accordance with the second exemplary embodiment at falling of the wearer.

FIG. 11 illustrates the inflation process of the airbag of the second exemplary embodiment.

FIG. 12 illustrates the inflation process of a modification of the airbag of the second exemplary embodiment.

FIG. 13 illustrates the inflation process of another modification of the airbag of the second exemplary embodiment.

DETAILED DESCRIPTION

Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings. However, the invention is not limited to the embodiments disclosed herein. All modifications within the appended claims and equivalents relative thereto are intended to be encompassed in the scope of the claims.

Referring to FIGS. 1A to 4, a wearable airbag device 10 in accordance with the first exemplary embodiment includes a gas generator 23, an airbag 30 inflatable with an inflation gas G fed from the gas generator 23, an operation control device 20 that includes a sensor part 21 for detecting a fall of the wearer 1 and is configured to actuate the gas generator 23, and a holding body 11 that is formed into a vest and holds the gas generator 23, the airbag 30 and the operation control device 20.

The holding body 11 is formed into a vest that is wearable on the upper body 1 a. The holding body 11 includes a left front portion 12 and a right front portion 13 for covering the front side of the upper body 1 a of the wearer 1 in combination, a back portion 14 for covering the back of the upper body 1 a of the wearer 1, and a fastening member 16 such as a zipper for fastening the inner edges 12 a and 13 a of the left front portion 12 and the right front portion 13 together. In other words, the left front portion 12 adjoins the back portion 14 on the front side of the left portion 14 b, and the right front portion 13 adjoins the back portion 14 on the front side of the right portion 14 c.

The operation control device 20 includes a sensor part 21 that includes an angular velocity sensor capable of sensing angular velocities around three axes in up and down, front and rear, and left and right directions, and an acceleration sensor capable of sensing accelerations in the three-axis directions. The operation control device 20 is configured to actuate the gas generator 23 in response to a signal fed from the sensor part 21 which has sensed a falling behavior different from a normal behavior of the wearer 1. More particularly, the operation control device 20 includes a determining means that is configured to determine based on various thresholds, and is configured to actuate the gas generator 23 upon sensing a fall of the wearer 1 based on the determination by the determining means. The operation control device 20 further includes a power source composed of a not-shown battery or the like for operation of the sensor part 21 and for emission of an actuating signal to the gas generator 23.

The operation control device 20 is stored in a not-shown cover or the like and disposed in a lower portion 14 d of and on an inner surface of the right portion 14 c in the back portion 14 of the holding body 11 so as not to be engaged with the clothing of the wearer 1, as can be seen in FIG. 1B.

The gas generator 23 contains an inflation gas G composed of carbon dioxide or the like in a compressed state. The gas generator 23 includes a not-shown initiator, a not-shown burst disc, a gas discharge portion 23 a disposed at the leading end, and a not-shown mounting member. The gas generator 23 is designed to actuate the initiator to break the burst disc so that the inflation gas G is discharged from the gas-discharge portion 23 a when fed with an actuating signal from the operation control device 20 that has sensed a fall of the wearer 1.

The wearable airbag device 10 of the first exemplary embodiment includes one gas generator 23. The gas generator 23 including the gas discharge portion 23 a is stored in a later-described lower inflatable portion 31 of the airbag 30, in a vicinity of an upper edge 33 a of a right portion 33 of the lower inflatable portion 31. The gas generator 23 is attached to the inner surface of the lower portion 14 d of the right portion 14 c in the back portion 14 of the holding body 11, where the operation control device 20 is disposed, with the use of the not-shown mounting member passed through the airbag 30.

The airbag 30 includes an inflatable portion that is inflatable with the inflation gas G. The inflatable portion includes a lower inflatable portion 31 that is disposed at a position in the holding body 11 capable of protecting the hip 2 of the wearer 1, an upper inflatable portion 41 that is disposed at a position in the holding body 11 capable of protecting the head 5 of the wearer 1, and a communicating portion 37 that is in gas communication with both of the lower inflatable portion 31 and upper inflatable portion 41. The airbag 30 is formed of a woven fabric of polyester, polyamide or the like into a bag, by sewing, OPW technology or the like, and has been subjected to gastight processing.

The lower inflatable portion 31 is disposed in a region extending over lower portions 14 d, 12 b, 13 b of the back portion 14, left front portion 12 and right front portion 13 of the holding body 11, and is configured to cover the hip 2, especially left and right trochanters 3 (3L, 3R) of femurs and surroundings, of the wearer 1 at deployment. The lower inflatable portion 31 includes a left portion 32 that is adapted to cover an outer side of the left trochanter 3L of femur when deployed, a right portion 33 that is adapted to cover an outer side of the right trochanter 3R of femur when deployed, and a central portion 34 that connects the left portion 32 and right portion 33 and has a reduced width in an up and down direction compared to the left portion 32 and right portion 33. Each of the left portion 32 and right portion 33 is configured to be inflated and deployed into a substantially rectangular board shape extending forward and rearward from a left/right side 2 a of the hip 2 of the wearer 1. Each of the left portion 32 and right portion 33 as deployed has a greater width in the up and down direction than the central portion 34 such that the lower edge 32 b/33 b is disposed farther downward than the central portion 34. In a standby (stored) state, each of the left portion 32 and right portion 33 is in a folded form that was formed by folding the left portion 32/right portion 33 in such a manner as to bring the lower edge 32 b/33 b close to the upper edge 32 a/33 a, more particularly, by invaginating the lower edge 32 b/33 b portion into the left portion 32/right portion 33.

The communicating portion 37 is in gas communication with the central portion 34 of the lower inflatable portion 31 by the lower end 37 b while in gas communication with the upper inflatable portion 41 by the upper end 37 a. The communicating portion 37 is attached to an inner surface of a central portion 14 a of the back portion 14 in the holding body 11.

The upper inflatable portion 41 is configured to be inflated into a substantially rectangular board shape that is greater in width in the left and right direction than the communicating portion 37 and capable of covering the head 5, especially the back 6 of the head, of the wearer 1 at airbag deployment. In the stored state, the upper inflatable portion 41 is in a folded form that was formed by folding the upper inflatable portion 41 in such a manner as to bring the upper edge 41 a close to the lower edge 41 b, more particularly, by invaginating the upper edge 41 a portion into the upper inflatable portion 41. The upper inflatable portion 41 is attached to an inner surface of a neck portion 15 disposed at the upper end portion of the back portion 14 in the holding body 11.

As best shown in FIG. 2B, the airbag 30 further includes, in the upper edges 32 a, 33 a of the lower inflatable portion 31, in the lower edge 41 b of the upper inflatable portion 41 and in the left and right edges 37 d of the communicating portion 37, a plurality of mounting tabs 30 a. The airbag 30 is attached to the inner surface of the holding body 11 by the mounting tabs 30 a by sewing or the like.

The airbag 30 includes, in the communicating portion 37, a regulating element 45 that regulates or controls the flow of inflation gas G so that the upper inflatable portion 41 is inflated after inflation of the lower inflatable portion 31.

The regulating element 45 in the first exemplary embodiment is composed of a valve 46 disposed in the communicating portion 37. The valve 46 is formed of a sheet material having flexibility composed of the same material as the woven fabric forming the airbag 30. The valve 46 has a substantially tapered tubular shape. As can be seen in FIGS. 1B and 2A, the valve 46 includes a tapered leading-end portion 46 a that is directed toward the lower inflatable portion 31, an outlet port 46 b of inflation gas G that is disposed at the tip end of the leading-end portion 46 a, a peripheral portion 46 c disposed in the periphery of the outlet port 46 b, and a base portion 46 d having an enlarged diameter and jointed entirely to an entire inner circumference of the communicating portion 37 by sewing or the like.

In a very early stage of airbag deployment in which the lower inflatable portion 31 starts to be inflated with an inflation gas G from the gas discharge portion 23 a of the gas generator 23, the leading-end portion 46 a of the valve 46 points toward the lower inflatable portion 31, and the peripheral portion 46 c in the periphery of the outlet port 46 b draws together and closes the outlet port 46 b, that is, the valve 46 is in a closed state, as can be seen in (A) and (B) of FIG. 4. Since the valve 46 is closed, the inflation gas G does not flow out of the lower inflatable portion 31. Thereafter, as an internal pressure of the lower inflatable portion 31 rises and surpasses a predetermined value, the peripheral portion 46 c reverses toward the upper inflatable portion 41, so the outlet port 46 b becomes open. That is, the valve 46 shifts to an open state from the closed state. Then the inflation gas G flows into the upper inflatable portion 41 from the lower inflatable portion 31 via the communicating portion 37.

The wearer 1 puts the wearable airbag device 10 (i.e. the holding body 11) in accordance with the first exemplary embodiment on the upper body 1 a using the fastening member 16. If the wearer 1 wearing the wearable airbag device 10 falls as can be seen in (A) and (B) of FIG. 3, the gas generator 23 is actuated and discharges an inflation gas G from the gas discharge portion 23 a to inflate the lower inflatable portion 31, as can be seen in (A) and (B) of FIG. 4. The airbag 30 of the first exemplary embodiment is configured so that the lower inflatable portion 31 for protecting the hip 2 of the wearer 1 is inflated prior to the upper inflatable portion 41 for protecting the head 5 due to the flow control of inflation gas G by the regulating element 45 (i.e. the valve 46), as can be seen in (A) and (B) of FIG. 4. After inflation of the lower inflatable portion 31, the upper inflatable portion 41 is fed with the inflation gas G and inflated for protecting the head 5, as can be seen in (C) of FIG. 4 and FIG. 2B.

When a wearer 1 falls, it is likely that the hip 2 hits the ground 8 first as shown in (A) and (B) of FIG. 3, then the head 5 hits the ground 8 as shown in (C) and (D) of FIG. 3. When the hip 2 hits the ground 8, the trochanter 3 (3L, 3R) of femur (FIGS. 1A, 1B) is prone to injury or fracture because it is prominent. Since the treatment of fracture of the trochanter 3 of femur takes a long time, it is important to protect the hip 2 in an initial stage of falling. The wearable airbag device 10 in accordance with the first exemplary embodiment is able to protect the hip 2 adequately by inflating the lower inflatable portion 31 prior to the upper inflatable portion 41 so that the lower inflatable portion 31 is deployed between the hip 2 and the ground 8, as can be seen in (B) of FIG. 3.

When the wearer 1 rolls on the ground 8 after the hip 2 hit the ground 8, he/she is likely to hit their head 5 on the ground 8, as can be seen in (C) and (D) of FIG. 3. The airbag 30 of the first exemplary embodiment is configured such that the valve 46 (i.e. the regulating element 45) is reversed and the outlet port 46 b is opened ((B) and (C) of FIG. 4) at rise of the internal pressure of the lower inflatable portion 31 having been inflated to protect the hip 2 so as to allow the inflation gas G to flow into the upper inflatable portion 41 and to deploy the upper inflatable portion 41 between the head 5 and ground 8 in a timely manner, as indicated with dashed-and-double-dotted lines in FIGS. 1A, 1B and as shown in FIG. 2B and in (C) and (D) of FIG. 3. Therefore, the airbag 30 is able to protect the head 5 of the wearer 1 adequately. The wearable airbag device 10 is able to make the above action occur easily even with only one gas generator 23 by controlling the timings of inflation of the lower inflatable portion 31 and upper inflatable portion 41 by the regulating element 45 disposed in the communicating portion 37.

Therefore, the wearable airbag device 10 in accordance with the first exemplary embodiment is able to protect the hip 2 and the head 5 of the wearer 1 adequately and each in a timely manner with the airbag 30 though it includes a limited number of (one) gas generator 23.

In the wearable airbag device 10 of the first exemplary embodiment, the gas discharge portion 23 a of the gas generator 23 that is configured to discharge the inflation gas G is disposed in the lower inflatable portion 31, and the regulating element 45 is configured to regulate the flow of the inflation gas G flowing toward the upper inflatable portion 41 from the lower inflatable portion 31.

This configuration will help inflate the lower inflatable portion 31 before the upper inflatable portion 41 starts to be inflated though the airbag device 10 includes only one gas generator 23. Therefore, the wearable airbag device 10 is able to protect the hip 2 quickly.

In the first exemplary embodiment, especially, the regulating element 45 is composed of the valve 46 that is disposed in the communicating portion 37 and formed of a sheet material having flexibility. The valve 46 is configured to shift from the closed state to the open state that allows the inflation gas G to flow toward the upper inflatable portion 41 when the internal pressure of the lower inflatable portion 31 surpasses a predetermined value.

With this configuration, the valve 46 in the closed state enables the lower inflatable portion 31 to secure a predetermined internal pressure before the upper inflatable portion 41 starts to be inflated. Therefore, the wearable airbag device 10 is able to protect the hip 2 quickly and stably.

The regulating element 45 should operate to regulate the flow of inflation gas G flowing toward the upper inflatable portion 41 from the lower inflatable portion 31 so that the lower inflatable portion 31 is inflated quickly and the upper inflatable portion 41 is inflated in a timely manner to protect the head 5.

To this end, the regulating element may be alternatively configured like a regulating element 45A or a regulating element 45B depicted respectively in FIGS. 5 and 6 and described as follows:

The regulating element 45A is composed of a constricted portion 48 formed by reducing an opening area of a part of the communicating portion 37.

In the airbag 30A with the constricted portion 48, when the gas generator 23 is actuated, an inflation gas G is discharged from the gas discharge portion 23 a into the lower inflatable portion 31, and the lower inflatable portion 31 is able to complete inflation before the upper inflatable portion 41 starts to inflate due to regulation of the flow of inflation gas G by the constricted portion 48, as can be seen in (A) and (B) of FIG. 5. Therefore, the airbag 30A is able to protect the hip 2 quickly and stably. Of course, when the lower inflatable portion 31 is fully inflated, the inflation gas G starts to flow toward the upper inflatable portion 41 via the constricted portion 48, and inflates the upper inflatable portion 41 as can be seen in (C) of FIG. 5, so that the upper inflatable portion 41 is able to protect the head 5.

In the airbag 30A depicted in FIG. 5, the constricted portion 48 having a reduced opening area is formed in an intermediate portion 37 c of the communicating portion 37 disposed between the upper end 37 a and the lower end 37 b of the communicating portion 37. Alternatively, the constricted portion may be composed of a communicating portion 37 itself that has a reduced opening area substantially over its entire length.

The regulating element 45B depicted in FIG. 6 is composed of one or more jointed portions 50 in which opposing portions of a circumferential wall of the communicating portion 37 are jointed together so as to reduce the opening area of the communicating portion 37. Each of the jointed portions 50 is configured to disjoint when the internal pressure of the lower inflatable portion 31 surpasses a predetermined value. Although the jointed portion 50 is composed of a sewn seam of breakable sewing threads 51, the jointed portion may also be formed with the use of adhesive, thermal welding or the like.

In the airbag 30B with the jointed portions 50, when the gas generator 23 is actuated, an inflation gas G is discharged from the gas discharge portion 23 a into the lower inflatable portion 31, and the lower inflatable portion 31 is able to complete inflation and secure a desired internal pressure before the upper inflatable portion 41 starts to inflate due to regulation of the flow of inflation gas G by the jointed portions 50, as can be seen in (A) and (B) of FIG. 6. Therefore, the airbag 30B is able to protect the hip 2 quickly and stably. Of course, when the lower inflatable portion 31 is fully inflated and the internal pressure of the lower inflatable portion 31 surpasses a predetermined value, the sewing threads 51 forming the jointed portions 50 break and the jointed portions 50 disjoint and stop blocking the gas flow toward the upper inflatable portion 41, so that the inflation gas G easily flows into the upper inflatable portion 41 via the communicating portion 37 and inflates the upper inflatable portion 41 as can be seen in (C) of FIG. 6, so that the upper inflatable portion 41 is able to protect the head 5.

In the wearable airbag device 10 of the foregoing embodiment, the gas discharge portion 23 a of the gas generator 23 is disposed in the lower inflatable portion 31 while the regulating element 45 is disposed in the communicating portion 37. The wearable airbag device in accordance with the first exemplary embodiment may alternatively modified like a wearable airbag device 10C depicted in FIG. 7. The wearable airbag device 10C includes one gas generator 23C, and a gas discharge portion 23 a of the gas generator 23 is disposed in the communicating portion 37 in such a manner as to deliver the inflation gas G to the lower inflatable portion 31. The regulating element 45C is composed of a valve 53 that is disposed in the communicating portion 37. The valve 53 is configured to regulate the flow of the inflation gas G toward the lower inflatable portion 31 and redirect the inflation gas G toward the upper inflatable portion 41 when the internal pressure of the lower inflatable portion 31 surpasses a predetermined value.

The valve 53 is formed of a sheet material having flexibility composed of the same material as the woven fabric forming the airbag 30C. The valve 53 has a substantially tapered tubular shape. The valve 53 is disposed at a portion in the communication portion 37 closer to the lower inflatable portion 31 than the gas discharge portion 23 a of the gas generator 23C. The valve 53 includes a tapered leading-end portion 53 a that is directed toward the lower inflatable portion 31, an outlet port 53 b of inflation gas G that is disposed at the tip end of the leading-end portion 53 a, a peripheral portion 53 c disposed in the periphery of the outlet port 53 b, and a base portion 53 d having an enlarged diameter and jointed entirely to an entire inner circumference of the communicating portion 37 by sewing or the like.

When an inflation gas G is discharged from the gas discharge portion 23 a of the gas generator 23, in a stage immediately after actuation of the gas generator 23, the valve 53 allows the inflation gas G to flow into the lower inflatable portion 31 via the outlet port 53 b as opened, so that the lower inflatable portion 31 is inflated as can be seen in (A) and (B) of FIG. 7. Thereafter, as an internal pressure of the lower inflatable portion 31 rises and surpasses a predetermined value, the peripheral portion 53 c closes the outlet port 53 b due to the internal pressure of the lower inflatable portion 31 (in other words, the valve 53 shifts to a closed state from an open state) as can be seen in (B) and (C) of FIG. 7, so that the valve 53 redirects the inflation gas G toward the upper inflatable portion 41.

This configuration is also able to inflate the lower inflatable portion 31 prior to the upper inflatable portion 41 and inflate the upper inflatable portion 41 after the lower inflatable portion 31 secured a predetermined internal pressure by flow control of inflation gas G by the regulating element 45C (i.e. the valve 53) although the wearable airbag device 10C includes a limited number of (one) gas generator 23. Therefore, the airbag 30C is able to protect the hip 2 quickly and stably, then protect the head 5 adequately.

A wearable airbag device 10D in accordance with the second exemplary embodiment is now described referring to FIGS. 8A to 11.

The wearable airbag device 10D of the second exemplary embodiment differ from the wearable airbag device 10 of the first exemplary embodiment in that an airbag 30D is composed of an outer bag 60 and an inner bag 70, and in that a gas generator 23D has a slightly smaller gas output than the gas generator 23 of the first exemplary embodiment. Since the structures of the holding body 11 and the operation control device 20 are common to the first exemplary embodiment and the second exemplary embodiment, those members will be assigned common reference signs and will not be described in detail.

The airbag 30D of the second exemplary embodiment includes an inner bag 70 and an outer bag 60 that covers an outer circumference of the inner bag 70. Each of the inner bag 70 and outer bag 60 is formed of a woven fabric of polyester, polyamide or the like similar to that forming the airbag 30 of the first exemplary embodiment, by sewing, OPW technology or the like.

As an inflatable portion, the inner bag 70 includes a lower inflatable portion 71 that is disposed at a position in the holding body 11 capable of protecting the hip 2 of the wearer 1, an upper inflatable portion 81 that is disposed at a position in the holding body 11 capable of protecting the head 5 of the wearer 1, and a communicating portion 77 that is in gas communication with both of the lower inflatable portion 71 and upper inflatable portion 81.

In a similar fashion to the lower inflatable portion 31 of the first exemplary embodiment, the lower inflatable portion 71 is disposed in a region extending over lower portions 14 d, 12 b, 13 b of the back portion 14, left front portion 12 and right front portion 13 of the holding body 11, and is configured to cover the hip 2, especially left and right trochanters 3 (3L, 3R) of femurs and surroundings, of the wearer 1 at deployment. The lower inflatable portion 71 includes a left portion 72 that is adapted to cover an outer side of the left trochanter 3L of femur when deployed, a right portion 73 that is adapted to cover an outer side of the right trochanter 3R of femur when deployed, and a central portion 74 that connects the left portion 72 and right portion 73 and has a reduced width in an up and down direction compared to the left portion 72 and right portion 73. Each of the left portion 72 and right portion 73 is configured to be inflated and deployed into a substantially rectangular board shape extending forward and rearward from the left/right side 2 a of the hip 2 of the wearer 1. Each of the left portion 72 and right portion 73 as deployed has a greater width in the up and down direction than the central portion 74 such that the lower edge 72 b/73 b is disposed farther downward than the central portion 74. In a standby (stored) state, each of the left portion 72 and right portion 73 is in a folded form that was formed by folding the left portion 72/right portion 73 in such a manner as to bring the lower edge 72 b/73 b close to the upper edge 72 a/73 a, more particularly, by invaginating the lower edge 72 b/73 b portion into the left portion 72/right portion 73.

The communicating portion 77 is in gas communication with the central portion 74 of the lower inflatable portion 71 by the lower end 77 b while in gas communication with the upper inflatable portion 81 by the upper end 77 a. The communicating portion 77 is stored in a later-described connecting covering portion 63 of the outer bag 60 and attached to an inner surface of the central portion 14 a of the back portion 14 in the holding body 11 in that state.

The upper inflatable portion 81 is configured to be inflated into a substantially rectangular board shape that is greater in width in the left and right direction than the communicating portion 77 and capable of covering the head 5, especially the back 6 of the head 5, of the wearer 1 at deployment of the inner bag 70.

The outer bag 60 has a bag shape capable of covering the outer circumference of the inner bag 70. The outer bag 60 includes a connecting covering portion 63 that is tubular in shape and covers an outer circumference of the communicating portion 77, an upper covering portion 65 that is continuous with an entire circumference of an upper end 63 a of the connecting covering portion 63 and is configured to cover an outer circumference of the upper inflatable portion 81 as inflated, and a lower covering portion 61 that is continuous with an entire circumference of a lower end 63 b of the connecting covering portion 63 and is configured to cover an outer circumference of the lower inflatable portion 71 as inflated.

The outer bag 60 further includes, in the upper edge 61 a of the lower inflatable portion 61, in the lower edge 65 b of the upper inflatable portion 65 and in the side edges 63 c of the connecting covering portion 63, a plurality of mounting tabs 60 a. The outer bag 60 is attached to the inner surface of the holding body 11 by the mounting tabs 60 a by sewing or the like.

The gas generator 23D including the gas discharge portion 23 a is stored in the lower inflatable portion 71 of the inner bag 70, in a vicinity of an upper edge 73 a of a right portion 73 of the lower inflatable portion 71. The gas generator 23D is attached to and fixed to the inner surface of the lower portion 14 d of the right portion in the back portion 14 of the holding body 11, where the operation control device 20 is disposed, with the use of a not-shown mounting member protruding from the gas generator 23D and passed through the inner bag 70 and outer bag 60.

As can be seen in FIGS. 8A, 8B and 9A, the airbag 30D in a standby state has a folded form so as not to protrude from the holding body 11. In the inner bag 70, the lower inflatable portion 71 is folded in such a manner that the lower edges 72 b, 73 b are brought closer to the upper edges 72 a, 73 a, and stored in the lower covering portion 61 of the outer bag 60 in that state. The upper inflatable portion 81 is brought closer to the lower inflatable portion 71 and stored in the connecting covering portion 63 of the outer bag 60. In the outer bag 60, the lower covering portion 61 is folded in such a manner that the lower edge 61 b is brought closer to the upper edge 61 a, and the upper covering portion 65 is folded in such a manner that the upper edge 65 a is brought closer to the lower edge 65 b.

The upper inflatable portion 81 of the inner bag 70 stored in the connecting covering portion 63 of the outer cover 60 is configured to move into the upper covering portion 65 and be inflated at rise of the internal pressure of the lower inflatable portion 71 caused by collision between the the lower inflatable portion 71 as fully inflated and the ground 8 at falling of the wearer 1.

The inner bag 70 of the second exemplary embodiment includes, in an intermediate portion 77 c in the up and down direction of the communicating portion 77, a regulating element 85 that regulates the flow of inflation gas G flowing toward the upper inflatable portion 81 from the lower inflatable portion 71. The regulating element 85 of this specific embodiment is composed of a constricted portion 87 that is formed by reducing an opening area of a part of the communicating portion 77.

The wearer 1 puts the wearable airbag device 10D (i.e. the holding body 11) in accordance with the second exemplary embodiment on the upper body 1 a using the fastening member 16. If the wearer 1 wearing the wearable airbag device 10D falls as shown in (A) and (B) of FIG. 10, the gas generator 23 is actuated and discharges an inflation gas G from the gas discharge portion 23 a to inflate the lower inflatable portion 71 of the inner bag 70 inside the lower covering portion 61 of the outer bag 60, as can be seen in (A) and (B) of FIG. 11, so that the hip 2 is protected. When the inflated lower inflatable portion 71 collides against the ground 8 through the intermediary of the lower covering portion 61, the inflation gas G stored in the lower inflatable portion 71 starts to flow toward the upper inflatable portion 81 via the communicating portion 77 covered by the connecting covering portion 63 of the outer cover 60. Then the upper inflatable portion 81 which has been stored inside the connecting covering portion 63 unfolds and extends into the upper covering portion 65, as can be seen in (B) and (C) of FIG. 11. At this time, if the wearer 1 further rolls and the head 5 comes close to the ground 8 as shown in (B) and (C) of FIG. 10, the pressure of the wearer 1 furthers the flow of the inflation gas G flowing from the lower inflatable portion 71 toward the upper inflatable portion 81 and unfolds the upper inflatable portion 81, so that the upper inflatable portion 81 extends into the upper covering portion 65 of the outer bag 60 and is deployed at a position for protecting the head 5, i.e. between the head 5 and the ground 8, as shown in (D) of FIG. 10. Therefore, the wearable airbag device 10D is able to protect the head 5 adequately. Although the wearable airbag device 10D includes one gas generator 23D in the lower inflatable portion 71 of the inner bag 70, the device 10D is able to inflate the lower inflatable portion 71 and the upper inflatable portion 81 in order in a timely manner in accordance with the behavior of the wearer 1 at falling that shifts from the hitting of the hip 2 on the ground 8 to the hitting of the head 5 on the ground 8, making use of the pressure given to the inner bag 70 from the ground 8 and the wearer 1. Therefore, the wearable airbag device 10D is able to protect the hip 2 and the head 5 adequately.

Therefore, the wearable airbag device 10D in accordance with the second exemplary embodiment is able to protect the hip 2 and the head 5 of the wearer 1 adequately and each in a timely manner with the airbag 30D though it includes a limited number of (one) gas generator 23D.

In the wearable airbag device 10D in accordance with the second exemplary embodiment, at the point of inflation of the upper inflatable portion 81 of the inner bag 70, the lower inflatable portion 71 of the inner bag 70 has finished protecting the hip 2, and therefore, it does not matter that the lower inflatable portion 71 does not contain a lot of inflation gas G because of moving of the gas to the upper inflatable portion 81. Therefore, even if the output power of the gas generator 23D is not high (in other words, even if the gas generator 23D is small and light in weight), the wearable airbag device 10D is able to make efficient use of the inflation gas G and protect the hip 2 and head 5 of the wearer 1 in a timely matter at falling of the wearer 1.

In the wearable airbag device 10D in accordance with the second exemplary embodiment, moreover, the airbag 30D further includes, in the communicating portion 77 of the inner bag 70, the regulating element 85 that is configured to control the flow of the inflation gas G to the upper inflatable portion 81 from the lower inflatable portion 71.

Since the regulating element 85 prevents the inflation gas G from flowing toward the upper inflatable portion 81 from the lower inflatable portion 71 in an initial stage of airbag deployment, the inflation of the lower inflatable portion 71 is prompted, so that the lower inflatable portion 71 is able to protect the hip 2 quickly.

In the second exemplary embodiment, the regulating element 85 is composed of the constricted portion 87 formed in the intermediate portion 77 c of the communicating portion 77 disposed between the upper end 77 a and the lower end 77 b of the communicating portion 77. Alternatively, the constricted portion may be composed of a communicating portion 77 itself that has a reduced opening area substantially over its entire length.

The regulating element may alternatively be configured like a regulating element 85A or a regulating element 85B depicted respectively in FIGS. 12 and 13 and described as follows:

The regulating element 85A depicted in FIG. 12 is composed of one or more folded portions 89 which are formed by folding the upper inflatable portion 81 and communicating portion 77. The folded portions 89 are stored inside the connecting covering portion 63 of the outer bag 60.

In the inner bag 70A with the regulating element 85A described above, the inflation gas G needs to unfold the folded portions 89 in the connecting covering portion 63 in order to go through the communicating portion 77 and flow into the upper inflatable portion 81. Therefore, the gas flow is regulated until unfolding of the folded portions 89, the inflation of the lower inflatable portion 71 is prompted, so that the lower inflatable portion 71 is able to protect the hip 2 quickly.

The regulating element 85B depicted in FIG. 13 is composed of one or more jointed portions 91 in which opposing portions of a circumferential wall of the communicating portion 77 are jointed together with sewing threads 92 so as to reduce the opening area of the communicating portion 77 of the inner bag 70B. Each of the jointed portions 91 is configured to disjoint when the internal pressure of the lower inflatable portion 71 surpasses a predetermined value. Although the jointed portion 91 is composed of a sewn seam of breakable sewing threads 92, the jointed portion may also be formed with the use of adhesive, thermal welding or the like.

In the inner bag 70B with the regulating element 85B described above, the inflation gas G needs to disjoint the jointed portions 91 in the communicating portion 77 in order to go through the communicating portion 77 and flow into the upper inflatable portion 81. Therefore, the gas flow is regulated until disjoint of the jointed portions 91, the inflation of the lower inflatable portion 71 is prompted, so that the lower inflatable portion 71 is able to protect the hip 2 quickly.

Further alternatively, the inner bag of the second exemplary embodiment may be formed of a stretch material so that the upper inflatable portion moves into the upper covering portion from the communicating portion along with an inflow of inflation gas.

Although the holding body 11 in the first and second exemplary embodiment is formed into a vest, the holding body 11 may be formed into a jacket with sleeves.

The wearable airbag devices in the first and second exemplary embodiments employ only one gas generator 23, 23D, respectively. However, the invention will not exclude the use of more than one gas generator as long as the number of the gas generator is limited corresponding to the volume of the airbag.

Furthermore, in the first and second exemplary embodiments, the gas generator 23, 23D is stored inside the airbag 30 or inner bag 70. Alternatively, however, it would be conceivable to locate only the gas discharge portion 23 a inside the airbag 30/inner bag 70 while locating the remaining portion of the gas generator outside of the airbag 30/inner bag 70 by providing a guide tube in the airbag 30/inner bag 70 for receiving the gas discharge portion or by inserting only the gas discharge portion 23 a into the airbag 30/inner bag 70 via a slit or the like formed in the airbag 30/inner bag 70.

The first exemplary embodiment of the present disclosure relates to a wearable airbag device including: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and is configured to discharge an inflation gas; and an airbag that is held by the holding body and includes an inflatable portion configured to be inflated with the inflation gas fed from the gas generator. The inflatable portion of the airbag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer; and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion. The airbag further includes, in the communicating portion, a regulating element that is configured to control a flow of the inflation gas so that the upper inflatable portion is inflated after inflation of the lower inflatable portion. The gas generator is configured to deliver the inflation gas more toward the lower inflatable portion than toward the upper inflatable portion.

The wearable airbag device in accordance with the first exemplary embodiment is configured to inflate and deploy the lower inflatable portion for protecting the hip of the wearer prior to the upper inflatable portion for protecting the head by the regulating element that control flow of inflation gas. After inflation of the lower inflatable portion, the upper inflatable portion is fed with the inflation gas and inflated for protecting the head. That is, when a wearer falls, it is likely that the hip hits the ground first, then the head hits the ground. When the hip hits the ground, the trochanter of femur is prone to injury or fracture because it is prominent. Since the treatment of fracture of the trochanter of femur takes a long time, it is important to protect the hip in an initial stage of falling. Thereafter, when the wearer further rolls on the ground after the hip hit the ground, they are likely to hit their head on the ground. The airbag of the first exemplary embodiment is configured to inflate and deploy the lower inflatable portion to protect the hip and then inflate and deploy the upper inflatable portion between the head and the ground to protect the head in a timely manner, respectively. The wearable airbag device in accordance with the first exemplary embodiment is able to make the above action occur easily even with only one gas generator by controlling the timings of inflation of the lower inflatable portion and upper inflatable portion by the gas generator that is configured to deliver the inflation gas more toward the lower inflatable portion than toward the upper inflatable portion, and by the regulating element disposed in the communicating portion.

Therefore, the wearable airbag device in accordance with the first exemplary embodiment is able to protect the hip and the head of the wearer adequately and each in a timely manner with the airbag though it includes a limited number of gas generator.

In one or more embodiments, the wearable airbag device may be configured such that: the gas generator includes a gas discharge portion that is configured to discharge the inflation gas; the gas discharge portion is disposed in the lower inflatable portion; and the regulating element is configured to regulate the flow of the inflation gas flowing toward the upper inflatable portion from the lower inflatable portion.

This configuration will help inflate the lower inflatable portion before the upper inflatable portion starts to be inflated even if the airbag device includes only one gas generator. Therefore, the airbag is able to protect the hip quickly.

In one or more embodiments, the regulating element may be composed of a valve that is disposed in the communicating portion and formed of a sheet material having flexibility, the valve being configured to shift from a closed state to an open state that allows the inflation gas to flow toward the upper inflatable portion when an internal pressure of the lower inflatable portion surpasses a predetermined value.

The valve in the closed state will enable the lower inflatable portion to secure a predetermined internal pressure before the upper inflatable portion starts to be inflated. Therefore, the airbag is able to protect the hip quickly and stably.

In one or more embodiments, the regulating element may be composed of a constricted portion in the communicating portion, the constricted portion having a reduced opening area compared to regions adjoining thereto in the communicating portion.

With the constricted portion, the lower inflatable portion will be able to complete inflation before the upper inflatable portion starts to inflate due to regulation of the flow of inflation gas by the constricted portion. Therefore, the airbag is able to protect the hip quickly and stably.

In one or more embodiments, the regulating element may also be composed of one or more jointed portions in which opposing portions of a circumferential wall of the communicating portion are jointed together so as to reduce an opening area of the communicating portion, each of the jointed portions being configured to disjoint when an internal pressure of the lower inflatable portion surpasses a predetermined value.

This configuration will also enable the lower inflatable portion to secure a predetermined internal pressure before the upper inflatable portion starts to be inflated. Therefore, the airbag is able to protect the hip quickly and stably.

In one or more embodiments, the wearable airbag device may be configured such that: the gas generator includes a gas discharge portion that is configured to discharge the inflation gas; the gas discharge portion is disposed in the communicating portion in such a manner as to deliver the inflation gas to the lower inflatable portion; and the regulating element is composed of a valve that is disposed in the communicating portion and configured to regulate the flow of the inflation gas toward the lower inflatable portion and redirect the inflation gas toward the upper inflatable portion when an internal pressure of the lower inflatable portion surpasses a predetermined value.

This configuration will also be able to inflate the lower inflatable portion first and inflate the upper inflatable portion after the lower inflatable portion secured a predetermined internal pressure by flow control of inflation gas by the valve even if the wearable airbag device includes only one gas generator. Therefore, the airbag is able to protect the hip quickly and stably, then protect the head adequately.

The second exemplary embodiment in the present disclosure relates to a wearable airbag device including: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and includes a gas discharge portion that is configured to discharge an inflation gas; and an airbag that is held by the holding body, the airbag including an inner bag that includes an inflatable portion configured to be inflated with an inflation gas fed from the gas generator, and an outer bag that has a bag shape and covers an outer circumference of the inner bag. The inflatable portion of the inner bag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer, and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion. The outer bag includes: a connecting covering portion that is tubular in shape and covers an outer circumference of the communicating portion of the inner bag; an upper covering portion that is continuous with an entire circumference of an upper end of the connecting covering portion and is configured to cover an outer circumference of the upper inflatable portion of the inner bag as inflated; and a lower covering portion that is continuous with an entire circumference of a lower end of the connecting covering portion and is configured to cover an outer circumference of the lower inflatable portion as inflated. The gas discharge portion of the gas generator is disposed in the lower inflatable portion of the inner bag so as to inflate the lower inflatable portion prior to the upper inflatable portion. The lower inflatable portion of the inner bag is stored inside the lower covering portion of the outer bag. The upper inflatable portion of the inner bag is stored in the connecting covering portion of the outer bag and is configured to move into the upper covering portion of the outer bag and be inflated at rise of an internal pressure of the lower inflatable portion caused by collision between the lower inflatable portion as fully inflated and the ground at falling of the wearer.

With the wearable airbag device in accordance with the second exemplary embodiment, if the wearer wearing the wearable airbag device falls and the gas generator is actuated, the gas generator discharges an inflation gas from the gas discharge portion to inflate the lower inflatable portion of the inner bag inside the lower covering portion of the outer bag, so that the hip is protected. When the inflated lower inflatable portion collides against the ground through the intermediary of the lower covering portion, the inflation gas stored in the lower inflatable portion starts to flow toward the upper inflatable portion via the communicating portion covered by the connecting covering portion of the outer cover. Then the upper inflatable portion which has been stored inside the connecting covering portion unfolds and extends into the upper covering portion. At this time, if the wearer further rolls and the head comes close to the ground, the pressure of the wearer makes the inflation gas in the lower inflatable portion flow toward the upper inflatable portion and unfolds the upper inflatable portion, so that the upper inflatable portion extends into the upper covering portion of the outer bag and is deployed at a position for protecting the head, i.e. between the head and the ground. Therefore, the airbag is able to protect the head adequately. Although the wearable airbag device includes one gas generator in the lower inflatable portion of the inner bag, the wearable airbag device is able to inflate the lower inflatable portion and the upper inflatable portion in order in a timely manner in accordance with the behavior of the wearer at falling that shifts from the hitting of the hip on the ground to the hitting of the head on the ground, making use of the pressure given to the inner bag from the ground.

Therefore, the wearable airbag device in accordance with the second exemplary embodiment is also able to protect the hip and the head of the wearer adequately and each in a timely manner with the airbag though it includes a limited number of gas generator. In the wearable airbag device in accordance with the second exemplary embodiment, moreover, at the point of inflation of the upper inflatable portion of the inner bag, the lower inflatable portion of the inner bag has finished protecting the hip, and therefore, it does not matter that the lower inflatable portion does not contain a lot of inflation gas because of moving of the gas to the upper inflatable portion. Therefore, even if the output power of the gas generator is not high, the wearable airbag device is able to make efficient use of the inflation gas and protect the hip and head of the wearer in a timely matter at falling of the wearer.

In one or more embodiment, the airbag of the above-described wearable airbag device may further include, in the communicating portion of the inner bag, a regulating element that is configured to regulate a flow of the inflation gas flowing toward the upper inflatable portion from the lower inflatable portion.

By regulating the gas flow flowing toward the upper inflatable portion from the lower inflatable portion, the regulating element will prompt the inflation of the lower inflatable portion so that the lower inflatable portion protects the hip quickly. 

What is claimed is:
 1. A wearable airbag device comprising: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and is configured to discharge an inflation gas; and an airbag that is held by the holding body and includes an inflatable portion configured to be inflated with the inflation gas fed from the gas generator, wherein the inflatable portion of the airbag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer; and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion; wherein the airbag further includes, in the communicating portion, a regulating element that is configured to control a flow of the inflation gas so that the upper inflatable portion is inflated after inflation of the lower inflatable portion; and wherein the gas generator is configured to deliver the inflation gas more toward the lower inflatable portion than toward the upper inflatable portion.
 2. The wearable airbag device of claim 1, wherein: the gas generator includes a gas discharge portion that is configured to discharge the inflation gas; the gas discharge portion is disposed in the lower inflatable portion; and the regulating element is configured to regulate the flow of the inflation gas flowing toward the upper inflatable portion from the lower inflatable portion.
 3. The wearable airbag device of claim 2, wherein the regulating element is composed of a valve that is disposed in the communicating portion and formed of a sheet material having flexibility, the valve being configured to shift from a closed state to an open state that allows the inflation gas to flow toward the upper inflatable portion when an internal pressure of the lower inflatable portion surpasses a predetermined value.
 4. The wearable airbag device of claim 2, wherein the regulating element is composed of a constricted portion in the communicating portion, the constricted portion having a reduced opening area compared to regions adjoining thereto in the communicating portion.
 5. The wearable airbag device of claim 2, wherein: the regulating element is composed of one or more jointed portions in which opposing portions of a circumferential wall of the communicating portion are jointed together so as to reduce an opening area of the communicating portion; and each of the jointed portions is configured to disjoint when an internal pressure of the lower inflatable portion surpasses a predetermined value.
 6. The wearable airbag device of claim 1, wherein: the gas generator includes a gas discharge portion that is configured to discharge the inflation gas; the gas discharge portion is disposed in the communicating portion in such a manner as to deliver the inflation gas to the lower inflatable portion; and the regulating element is composed of a valve that is disposed in the communicating portion and configured to regulate the flow of the inflation gas toward the lower inflatable portion and redirect the inflation gas toward the upper inflatable portion when an internal pressure of the lower inflatable portion surpasses a predetermined value.
 7. A wearable airbag device comprising: a holding body that is adapted to be worn by a wearer; a gas generator that is held by the holding body and includes a gas discharge portion that is configured to discharge an inflation gas; and an airbag that is held by the holding body, the airbag including an inner bag that includes an inflatable portion configured to be inflated with an inflation gas fed from the gas generator, and an outer bag that has a bag shape and covers an outer circumference of the inner bag, wherein the inflatable portion of the inner bag includes: a lower inflatable portion that is disposed at a position in the holding body capable of protecting the hip of the wearer; an upper inflatable portion that is disposed at a position in the holding body capable of protecting the head of the wearer; and a communicating portion that is in gas communication with both of the lower inflatable portion and the upper inflatable portion; wherein the outer bag includes: a connecting covering portion that is tubular in shape and covers an outer circumference of the communicating portion of the inner bag; an upper covering portion that is continuous with an entire circumference of an upper end of the connecting covering portion and is configured to cover an outer circumference of the upper inflatable portion of the inner bag as inflated; and a lower covering portion that is continuous with an entire circumference of a lower end of the connecting covering portion and is configured to cover an outer circumference of the lower inflatable portion as inflated; wherein the gas discharge portion of the gas generator is disposed in the lower inflatable portion of the inner bag so as to inflate the lower inflatable portion prior to the upper inflatable portion; wherein the lower inflatable portion of the inner bag is stored inside the lower covering portion of the outer bag; and wherein the upper inflatable portion of the inner bag is stored in the connecting covering portion of the outer bag and is configured to move into the upper covering portion of the outer bag and be inflated at rise of an internal pressure of the lower inflatable portion caused by collision between the lower inflatable portion as fully inflated and the ground at falling of the wearer.
 8. The wearable airbag device of claim 7, wherein the airbag further includes, in the communicating portion of the inner bag, a regulating element that is configured to regulate a flow of the inflation gas flowing toward the upper inflatable portion from the lower inflatable portion. 